Heat resistant coating for solder connections

ABSTRACT

A high temperature resistant coating composition for solder connection including a mixture of room temperature vulcanizing rubber having a viscosity rating of 250 poise and selective insulators including magnesium hydroxide, magnesium carbonate, asbestos, mica, barium sulfate and calcium carbonate for shielding the connection from a heat source of a predetermined intensity for a predetermined time.

United States Patent 1451 1 June 6, 1972 Smestad et al.

[541 HEAT RESISTANT COATING FOR SOLDER CONNECTIONS [72] Inventors: Dale E, Smestad, Coltage Grove, Minn.; Nelson E. Quackenbush, Costa Mesa, Calif.

The United States of America as [73] Assignee:

represented by the Secretary of the Army [22] Filed: Jan. 27, 1971 21 ApphNo; 110,251

[52] U.S. Cl ..260/37 SB [51] lnt.Cl ...C08g 51/04 [58] Field of Search ..260/37 SB [5 6] References Cited UNITED STATES PATENTS 3,151,099 9/1964 Ceyzeriat et al ..260/37 SB X 3,050,485 8/1962 Nitzsche et al. ..260/37 SB X 3,032,528 5/1962 Nitzsche et a]. ...260/37 SB X 3,464,951 9/1969 Hittmar et al. ..260/37 SB Primary Examiner-Lewis T. Jacobs Attorney-Harry M. Saragovitz, Edward J. Kelly, Herbert Berl and Charles R. Carter [57] ABSTRACT 1 Claim, No Drawings HEAT RESISTANT COATING FOR SOLDER CONNECTIONS BACKGROUND OF THE INVENTION This invention relates to the field of heat resistant coatings. Previous coatings consisting of RTV-60'silicone rubber with THEMOLITE 12 burst into flame in less than 16 seconds when exposed to a 2,000 F heat source at a distance of oneeighth inch and interfere with the missile guidance system.

SUMMARY OF THE INVENTION This invention provides a coating for protecting solder connections having a flame burst factor of approximately eight times that previously known and used.

DESCRIPTION OF THE PREFERRED EMBODIMENT Solder connections are provided with a heat resistant coating comprised of mixture of room temperature vulcanizing silicone rubber have a viscosity rating of 250 poise and selective heat insulators including magnesium hydroxide, magnesium carbonate, asbestos, mica, barium sulfate and calcium carbonate. Three grades of mica; 325 mesh water ground, hand pulverized 16 mesh vermiculite and a micronized mica have similar capabilities.

A typical coating application comprises:

Parts by Weight 250 Poise silicone rubber Mica-325 20 Asbestos I We claim: 

